When you need pressure vessels for hazardous material transportation, it's essential that the tanks you use are durable and secure. Any time you're handling contents that need to be under high pressure, any weakness in the seams can be a potential safety threat. For this reason, you should test your pressure tanks frequently to ensure that they are stable and safe for transportation. Here is an overview of hydrostatic testing to help you understand what you can expect from your first tank test.
Overview of Hydrostatic Testing
Hydrostatic testing is a process of putting a pressure tank into a test jacket. The jacket is filled with water to test the penetration of the tank seams. Once you secure the pressure tank inside the testing system, a predetermined level of water pressure will be applied inside your pressure tank. As this happens, the container expands. The testing facility measures the rate of expansion.
The calculation of this expansion rate is typically used as part of the assessment of the tank's condition. Additionally, the testing technicians will need to physically inspect both the interior and exterior of the tank for indications of any weakness or wear.
How Often Should You Do This?
For most pressure tanks, you'll only need to do hydrostatic testing every couple of years. In most cases, the testing interval will be varied depending on the tank's construction and purpose. The regulatory agency that is responsible for whatever material you transport will tell you what the inspection requirements are for your system.
For example, you need to have SCBA tanks tested every three to five years. The fiberglass and Kevlar-wrapped tanks usually need to be tested more frequently, while most other tanks can safely go five years between testing. It is important that you have these tests done on time throughout the duration of the tank's usable life.
About the Usable Life
The tank manufacturer will tell you what the recommended life of the tank is so that you can monitor the age of each tank. When the pressure tank reaches the end of its usable life, it needs to be put out of service. In most cases, testing companies won't even consider running a hydro-test on a tank that's reached the end of its lifespan, so you can't be sure that it's safe to use. If there is any visible damage or the tank's been exposed to intense heat, it's time to retire it. Inspect the tank visually every time you use it for signs of physical damage, missing decals or other issues.
Completing Your Visual Inspection
In most cases, the testing company will conduct a thorough visual inspection of the tank. When possible, this includes both the interior and the exterior of the tank. If you use small tanks or portable units, you won't likely be able to conduct interior inspections, but with large tanks, the interior exam is essential.
When you inspect the interior cavity of a pressure tank, you'll want to check out the cylinder valve to ensure that it's free of corrosion. This gives you the confidence that the valve will open when you need it. Once you've removed the valve to inspect it, you can then use a mirror and light inside the cylinder to inspect the surface of the interior. Check for any damage or defects in both the tank and the neck or shoulder section.
Any time you're using pressure tanks, you need to be confident that your tanks are secure. These routine tests are the best way to verify that your tanks will hold up to the pressure that they have to withstand. With these tips, you can protect your tanks and everyone handling them from serious risks. For more information on maintaining your tanks, contact a pressure vessel fabrication company.